People with blood type A are at significantly higher risk of developing severe Covid-19, according to a study that has teased out the genetic factors that may explain why some people are so much worse affected by the virus.
The research, accepted for publication in a peer-reviewed journal, looked at the genomes of more than 1,600 people admitted to hospital with Covid-19 who needed help breathing, and compared them with those who had not contracted the disease.
Those who had blood type A appeared to be as much as 50 per cent more likely to need oxygen or a ventilator. About 42 per cent of Britons have blood type A.
The finding adds to other evidence in China that suggested blood type, which
